Track format and version info for durable data formats
Check configuration entries in common storage formats
Use specific exception for version mismatch errors
Fix common versioning methods
Customize error reporting for connection failed exceptions in CLI
Merge branch 'versioned-formats' of github.com:dwins/GeoGit into dwins-versioned-formats

Conflicts:
	src/core/src/main/java/org/geogit/repository/Repository.java
Make RepositoryConnectionException a checked exception as its something you might expect to happen